* A new variant of memblock_virt_alloc_* allocations:memblock_virt_alloc_try_nid_raw() - Does not zero the allocated memory - Does not panic if request cannot be satisfied

* optimize early system hash allocations

Clients can call alloc_large_system_hash() with flag: HASH_ZERO to specifythat memory that was allocated for system hash needs to be zeroed,otherwise the memory does not need to be zeroed, and client will initializeit.

If memory does not need to be zero'd, call the newmemblock_virt_alloc_raw() interface, and thus improve the boot performance.

* debug for raw alloctor

When CONFIG_DEBUG_VM is enabled, this patch sets all the memory that isreturned by memblock_virt_alloc_try_nid_raw() to ones to ensure that noplaces excpect zeroed memory.